Some Thanks for Professor Olofsson
| November 25, 2008 | Posted by Dave S. under Intelligent Design |
I’m halfway through mathematics Professor Peter Olofsson’s essay titled Probability, Statistics, Evolution, and Intelligent Design which originally appeared in the journal Chance.
The first thing I want to thank PO for is stating this early on:
Although [religion] is of interest in its own right, in fairness to ID proponents, it should be pointed out that many of them do not employ religious arguments against evolution and this article does not deal with issues of faith and religion.
The second thing I’d like to thank him for is describing ID as a valid scientific hypothesis in the discussion of the explanatory filter and the flagellum. PO brings up the same argument I’ve always pointed out when he talks about the rejection region for biological applications of the filter and the inability to bound it without doubt. I describe the same problem as that of, I think, a better term also used by Dembski called “probabilistic resources”. How can we ever possibly know some undiscovered pathway for law and chance to have assembled the flagellum doesn’t exist? The short answer is we cannot. We don’t know what we don’t know and we can’t calculate a probability for an unknown. This is in fact employing a valid “chance of the gaps” argument by PO.
The thing of it is there are lots of theories and hypotheses in science that are not provable because it is impossible in principle to rule out the unknown or the unobserved. Karl Popper famously stated how something cannot be provable but remain a valid scientific hypothesis. He illustrated it famously with a then mythical black swan. He gave the hypothesis “There are no black swans in nature.” He said this was a valid hypothesis because while it could never be proven true, that it was impossible to say all of nature was searched and no black swan possibly overlooked, the hypothesis can be disproven (falsified) by the observation of just one single black swan. In the meantime it was a valid hypothesis because it explained the known facts – millions of swans observed and none were black. A black swan in fact was eventually observed and science worked as it should – the black swan hypothesis was falsified.
So we have the ID hypothesis for the flagellum stated as “There are no unintelligent processes which can produce a complex machine (like a flagellum) in nature”. I have stated the ID hypothesis this way many times here. It is a perfectly valid scientific hypothesis which cannot be proven but can be falsified by observing just one unintelligent process producing such a machine. In the meantime we know that intelligence can produce complex machines. You’re reading this on one example of a complex machine which the explanatory filter would also predict is virtually impossible to have come about by law and chance alone.
I just glanced at the second half of the PO essay which addresses Behe’s “The Edge of Evolution”. I trust it rests on the same argument that the failure to observe any novel complex machines arising in the malaria parasite does not prove anything. I agree that it proves nothing. However, that doesn’t mean it doesn’t offer more evidence in favor of the ID hypothesis stated in the paragraph above. ID predicts that no complex machines would originate in even 10^30 reproductive opportunities for mutation and selection. Law and chance handily explains what was observed and what was observed fell far, far short of producing any significant machine-like complexity. What this represents is what Behe describes as probably the biggest real world test of evolution by chance and necessity ever witnessed. It validated microevolution by producing some small useful novelties but failed utterly to produce anything greater than what was predicted by known law and chance. No unknowns showed up. No black swan was observed.
The observations surrounding the malaria parasite could have, at least in principle, falsified the ID hypothesis. But it didn’t. So chalk up a successful prediction for ID.
tribune7[323],
You say that they are, Dembski says that they are not. I can only conclude that you disagree.
Sal Gal[321],
Let me repeat Demsbki’s answer: we rule out all hypotheses with p>1/2 by taking Caputo’s word (my emphasis because I think it’s pretty weak). My answer is that we can’t rule out all these hypotheses but it doesn’t matter, because he could also have cheated by using nonuniform chance. There is no need to insist on ruling out all chance hypotheses and infer “design” but that’s what the EF insists upon.
clarification:
I said:
“If the sequence can be produced by a simplisitic process then its only the probability of that simplistic process that is relevant, IMO – not the uncompressed length of the output.”
I meant that that is what is relevant in reality, not the design inference. But I guess you’ve given me some information I solicited previously if you’re confirming that the size (in bits) of a process capable of generating a string is not relevant in I.D, only the uncompressed length of the generated string itself.
gpuccio:
another clarification [329]
I wrote:
That I believe is where the argument from ignorance comes in in ID. Dembski would grant that “Sure a mechanism could cause this – but if you think there is one, you have to point it out, otherwise we’re going to assume its Intelligence”, where for him, Intelligence is something other than mechanism (or at least historically it has been for him).
Sometimes I think I actually agree with Dembski, and he is just incapable of expressing his ideas in a succinct way.
I understand, as I alluded to in 316, that if you trace back the mechanistic causes for something, that you will eventually hit something that wasn’t caused by a mechanism. At that point I do agree that all you have left as an explanation is blind chance or something else. If ID want’s to call this “something else” “Intelligent Design” that’s fine. But that doesn’t mean humans themselves operate on the basis of some nebulous unspecifiable thing. And let’s be clear – for ID, Intelligence is unspecifiable as it cannot be characterized as a mechanism for them. And just to repeat what I said in 316, whatever that first cause is it could have just existed forever, so you don’t even have to invoke “Intelligent Design” as a cause for it.
OK that’s it hopefully.
I have to clarify the following as well or someone will misunderstand [329]:
“If the sequence can be produced by a simplistic process then its only the probability of that simplistic process that is relevant, IMO – not the uncompressed length of the output.”
By simplistic process I don’t mean flipping a coin. I mean any simplistic process that could generate the string 100% of the time. “Necessity” in ID parlance.
PO[302]:
If you are willing to accept a test that is 97% reliable, then you will get false positives 3% of the time. If you use the UPB, you’re saying you won’t accept false positives. When the conditional hypothesis assumes a ‘normal’ population, then why would you want to accept false positives.
Two questions for you:
(1) According to Shandin, the true probability of getting a false positive is around 60%. Does that mean if the test were conducted twice on the same individual that the likelihood of that person getting a false positive 36%.
(2) For the posterior distribution you graphed, you’ve said that the cumulative porbability for p<=1/2 of 10^-11 is a level you consider too low to be likely. IOW, you reject it. Now the cumulative probability for p=.1, or p=.2 or .3 or .4 would all be lower. Would you reject those probabilities as well?
gpuccio [329,326]
I wrote:
“I hope you didn’t mean that humans have some general ability to distinguish compressible sequences from non-compressible ones, because no such ability exists anywhere.”
Let it not be said I can’t comprehend someone else’s point of view.
Upon reflection, I do understand that humans see patterns (compressible sequences) in things. We look for patterns. If we don’t discern a pattern in something, then for us it is noise (i.e. uncompressible) whether it is in reality or not. Furthermore, it seems to me that the patterns we perceive are often internal to us, that is we see patterns dictated by the patterns inherent in our internal coginitive and sensory makeup, which serve to filter out all but what they are capable of detecting.
This is all mechanistic, not some unexplained attribute of a nonmechanism, i.e. “Intelligent Agency”, IMO.
PaV[336],you won’t accept false positives.
I challenge the notion that there can be any empirical basis for saying that something that is not empirically observable causes the empirical distribution to deviate from the average. In the scenario of an indifferent creator of distributions, the uniform distribution is no more likely than any other. One must actually violate the Principle of Indifference to say that the data should be distributed in one way, and not another.
But there is a reality and this includes the existence of design. Attempts to quantify it are certainly not beyond the pale.
And I suspect Dembski’s methods have grounds for improvement — it is a fairly new thing, after all — but it is a pretty solid at bat.
You have to bring something non-empirical to the table to argue that empirical distributions should “look” one way and not another.
Sal Gal, that almost sounds like something Godel would say
But then again he went ahead and proved God anyway.
I am here to say that the only important things I know are unspeakable absurdities. They are a matter of private experience, not empirical observation or proof.
I agree with this. And unlike Godel, ID will not prove God nor is it designed to do so.
It will, however, illustrate the dangerous and cruel absurdity that society should be predicated on the belief that everything happened by accident and that there is no absolute purpose for our existence.
PaV[336],
Pleae ignore [338], I pressed return by mistake. You write
Well, you wouldn’t, but everybody isn’t normal. You have a population that is composed of normals and schizophrenics and you have two conditional probabilities, one for normals and one for schizophrenics. Among the normals, 3% test positive and among the schizophrenics, 97% test positive. As there are so few schizophrenics, most positive cases are actually miclassified normals. It’s a common problem in any type of screening.
Good question. No, the 36% (60% of 60%) would assume independence. Here, an individual tested twice would likely get the same test result twice (although that of course depends on the test and I don’t know what it is) so the false-positive rate would still be 60%.
(2) Yes.
PO, you see where PaV is going here. By getting you to admit that you would “reject” if p=.1, or .2 or .3 or .4, he will say that these constitute an implicit “rejection region.” Can you please respond to this “implicit” logical trap?
By the way, what’s often done in screenings for a disease is to first use a test with high sensitivity (will catch most disease cases but also many normal cases). Then the positive cases are restested with another test that has higher specificity (will weed out most false positives). The reason for not using the second test from the beginning is that it’s more expensive or time-consuming. I have personal experience in testing for TB for my green card application. First I tested positive with the skin test because I’d been vaccinated which gives a lot of false positives. Then I was cleared with a chest X ray. More specific because it actually looks at the lungs and is not affected by previous vaccinations.
RoyK[341],
I know, but I have already explained to him in an email the difference between a rejection region and a “rejection region.” He said I shouldn’t expect a reply but I still hope he read it. We can also look back at Mark Frank’s comment [237] or my comments [276] and [280]. I said I wouldn’t continue this debate but I reneged because PaV asked questions that I can answer. We’ll see how much stamina I have!
I’d love a free online statistics correspondence course…
gpuccio, if you’re still around:
I intended to reply to all your criticism but we haven’t even made it to Behe yet. It usually happens and the last time I debated at UD, we set a length record (the “Archie Bunker” thread). I have comments about Behe as well but I think we’ll take them “off the air” if you’re still interested.
IDskeptic[344],
It’s free, it’s online, and it might end abruptly at any time!
This discussion continues at a new thread Barry A created.
Thanks, Barry.